The present invention relates to stacking of sheets within sheet feeders and particularly to a separation apparatus for use with a recirculating sheet feeder. The recirculating sheet feeder described herein also may be utilized as a stream feeder, or changed according to the operator's requirements to a set generating mode where multiple copy sets are produced.
A recirculating sheet feeder is one which is particularly suited for mounting upon a copier. The typical copier has a horizontally positioned glass platen over which sheets are fed successively beneath the feeder, after having been separated from a stack of sheets located at the top of the feeder.
The original sheet stack is typically loaded with the first document on top, face up. From this stack each sheet is separated, transported and positioned face down upon the illumination station, overlying the glass platen of the copier. The sheets are generally automatically fed seriatim to the glass platen where they are temporarily registered and positioned in an appropriate processing station such as over the copier optics and illumination system. Immediately thereafter, the sheets are transported away from the registration position on the platen processing station and are conveyed back to the stacking area, which is located at the top of the feeder apparatus.
Within the typical recirculating feeder, there are many instrumentalities included to facilitate the automatic sheet handling capabilities of the device. The present invention is particularly considered to be one of the important functional devices of the feeder since it serves to separate the original sheets in sets as required to produce multiple sets of copies as desired by the machine operator. The separator mechanism endlessly separates the sheets being singly fed from the original stack from those being forwarded back to the stack support after exposure at the process station.
At such time that the complete original sheet stack has been fed to the platen and returned, the sheet set separator device automatically resets to its original starting position for initiation of another copy set. Each cycle of the separator in effect represents a copy set, and is therefore countable by means of appropriate sensing and counting apparatus which monitors the separator cycles. The cycles counted from the separator device count down through controls provided within the copier until the count agrees with the original program for copy sets as required by the operator.